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591 Uppsatser om Wood fuels - Sida 29 av 40

Svamparnas roller i svenska barrskogsekosystem : hur ser kunskapsläget ut hos några olika grupper människor?

Fungi are everywhere around us and recently, there has been an increased interest in their role and importance in the forest. The fungi have several strategies to acquire energy and nutrition; one example is a mutual symbiosis with trees and plants - another being dissolving organic materials. Attempts have been made to better understand the circulation of nutrition in coniferous forests, and how fungi cooperate. Trees and plants have adapted with mycorrhizae and are now interdependent which is important to consider in forestry. A great number of fungi depend on dead wood and old trees to set fruiting bodies and spread further. These fungi also create environments for other species, such as birds and insects. The vegetation of a forest is determined by a series of factors; tree species, how old the forest is, soil type, as well as the ability of the fungal spores to spread and establish. Furthermore, in determining vegetation, the fungi?s ability to compete in the soil matters. These factors are nearly unexplored. Researching fungi knowledge and interest, a survey was distributed to five groups of people. The groups included forest owners, high school teachers, high school students, senior citizens, and a fifth group - ?o he ? - consisting of people of mixed ages and backgrounds.

Fiberföstärkning av Limträbalkar

Glulam is a product that was engineered to make use of timber in a more efficient way. Bychoosing timber of similar quality and discarding natural defects during production, thedevelopment of a stronger cross-section is achieved.Carbon fiber is a relatively new material with a high tension capacity. This feature is used toexamine how the bending capacity of the beams improve by adhering carbon fiber laminateson the lower edge of the beamsThe strength of the material is tested with three experiments: carbon fiber on the bottom of thebeam (a), carbon fiber attached to the lower sides of the beam (b) and carbon fiber in thebeam, covered with a layer of wood (c)The results show that the first case, where the carbon fiber is attached to the bottom of thebeam, gave the best result with an increase in capacity of 59 % compared to the nonreinforcedcontrol. The other two cases also show an improvement in capacity, beam-type 3had a capacity increase of 47% and beam-type 4 increased with 25 %Tests were also made with glulam beams reinforced with fiberglass, but these tests were notanalyzed in depth because the purpose was to compare the capacity to carbon fiber. Thisbeam improved its capacity by 40.3%.The tests show that carbon fiber as a reinforcement material for glulam is a good choice whenthere is a requirement for stronger cross-sections in both new production and renovation ofold buildings.

Optisk undersökning av dieselsprayer från en höghastighetsroterande insprutare

There have been changes in Earth?s climate system on both global and regional scale since the pre-industrial era and some of these changes are due to human activities such as the combustion of fossil fuels. This calls for the development of engines with a higher efficiency and less harmful emissions. One interesting concept is the Homogeneous Charge Compression Ignition (HCCI) engine, which has the advantages of potentially low emissions combined with high efficiency. However, HCCI with diesel fuel requires a relatively long fuel/air mixing time to ensure a "homogenous" charge.

Den syd?stg?tska d?rromfattningen: en unders?kning av Kisa tingshus d?rromfattning

Kisa Courthouse in the south of ?sterg?tland is a house built in the early 19th century with a typical neoclassical style. With clearly regular symmetrical wooden facade scheme with a central main entrance. The main entrance is a wooden double door with richly decorated portico. the crown moulding above the door consists of a band of dentils with a cornice moulding at the top.

Energisäkerheten för fjärrvärmeanläggningars bränsletillförsel i Mälardalsområdet

There are several energy systems in the Swedish society and to ensure the comfort and health of the citizens it is of importance that the different energy systems are functioning properly. District heating is one of these energy systems and many household depend only on district heating to warm up their homes. District heating is dependent on several processes where every step needs to function in order to deliver the produced heat to the end consumer. Previous studies have investigated the distribution of district heating and how to make customers choose district heating as their heating method. The supply of fuel to the district heating plant has not been studied as much, even though it is an important part of the whole system. This thesis is a part of the project NORD-STAR (Nordic Strategic Adaption Research), which has focused on climate adaption in the Nordic countries.

Design av utomhusträdgård i Dubai :

To plan and build a garden in Dubai has other conditions and challenges than what you experience in Sweden. The heat, wind and lack of water makes the need for durable plants, a good design and landscaping important if you want to have the opportunity to use your garden during most of the year. The soil is poor of nutrients, alkaline and sometimes saline, witch makes supplying the soil with organic material and various fertilizers necessary if you want to be able to plant a bigger range of plant material in your garden. Another important part is to provide your garden with a good irrigation system that should be put into the ground before planting so that the plants are given a more even irrigation. It?s relatively green scenery you meet and to me it?s in a way surprising since the country with its climate is rather harsh for the purpose of supporting plant life.

De Paard - Visions of Playtopia

Playsam in Kalmar AB are world famous for their design of the toys they sell. Together with their CEO Carl Zedig the goal was to find a new product for the company.  The process has far from been linear, I started off in one direction, got rejected, turned another way and we finally decided to create a rocking horse in a De Stijl style. At the same time taking consideration of the demands from Playsam and myself.Playsam?s products are archetypes of ordinary objects around us such as the car or the aeroplane. The company mainly produces its toys in wood and the stylized shape together with the blank painted surface has become a hallmark for them.De Stijl, the Dutch art movement containing artists, designers and architects such as Piet Mondrian, Theo van Doesburg and Gerrit Rietveld.

Flygburen laserskanning kopplat till skördarmätning för datainsamling till operativ planering :

The requirements for operative planning activities are increasing. The forest industry wants to gain better control over wood flow. A felling that is more market adjusted is desirable. However, this causes problems in the operative planning process because of the data collection methods used today. Data about timber assortments and data about the distribution of the tree diameter, etc., are often lacking. Airborne laser scanning is used to a greater extent than before for estimation of forest variables and should perhaps be used to the same extent in operative planning activities as well.

Bakterietillväxt i strömedel till mjölkkor

The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores. In this literature study the most commonly used bedding materials; straw, sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied. Most bacteria need humidity and prefer a quite high water activity to be able to grow.

Budgetstöd : relationen till de svenska biståndspolitiska målen: att skapa förutsättningar för de fattiga att själva driva sin utveckling, uppnå jämlika förhållanden mellan givare och mottagare och fattigdomsbekämpning

There's no doubt today that mankind has contributed to the changing climate byher use of fossil fuels. This must change in the nearby future. The Europeanleaders are expressing concern that renewable energy sources are not beingused to their full potential. The 2001/77/EC Directive on Electricity Productionfrom Renewable Energy Sources was accepted in 2001 to encourage thedevelopment of energy production from renewable sources, which isconsidered a step towards the fulfillment of the goal of the Union, that 12% ofthe gross energy consumption should come from renewable energy sources bythe year 2010.The objective of this thesis is to illuminate the common legislation of the EUregarding renewable energy with regard to goal fulfillment, judicial quality,conflicts with other goals of the EU and other faults. The objective is reachedby a hermeneutic study in which interpretation of written text is the mainmethod.

Systemanalys av skogsbränsletransporter :

At the end of 70s and the beginning of 80s, 18 terminals was built and used for chipping wood residue from clear cuttings. Most of the terminals was terminated before the 2000s but with the high oil- and energy prices that we can see today there might be a place for these terminals again. The goal with the study was to analyze and compare economical differences between 5 different logistical systems, collected data was used with a set of formulas. The systems include long range transport of slash, chips and bundles. Three of the systems include transport by lorry to industry the last two includes a terminal with access to train transport.

Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket efter den nya skogsvårdslagen

Detta arbete har undersökt skillnaderna mellan den nuvarande skogsvårdslagen och den föregående. Undersökningen har bestått av två delar, där ena delen är en litteraturstudie av lagarna och den andra är en fältstudie av metoder för att mäta naturhänsynsförändring. Som komplement till fältstudien har en litteraturstudie av undersökningsparametranas naturvårdsnytta. Litteraturstudien av lagarna gick till på följande sätt, inledningen av båda lagarna och hänsynsparagraferna har lästs och jämförts. Fältstudie har gjorts efter metoder som har arbetats fram och sedan testats i fält.

Stråkröjning och skogsbränsleuttag i unga granbestånd jämfört med konventionella metoder : Två fältstudier vid Asa försökspark

Den här uppsatsen grundar sig på två fältstudier i nyutlagda demonstrationsförsök på Asa försökspark som ska användas i utbildningssyfte. Studie 1 bestod av försöksytor i ett 13 år gammalt bestånd som röjts till samma röjningsförband men med tre skilda metoder; motormanuell selektiv röjning, maskinell stråkröjning och som en kombination av bägge metoderna. Syftet var att beskriva det nuvarande tillståndet, simulera fram prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser fram till och med första gallring och jämföra de olika metoderna med varandra. Studie 2 bestod av försöksytor i ett 23 år gammalt eftersatt bestånd där fyra olika åtgärder testades; ingen röjning innan gallring, underröjning i samband med gallring, sen röjning och skogsbränsleuttag. Syftet var även här att jämföra de olika metoderna med varandra genom beskrivning av det nuvarande tillståndet, göra prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser vid första gallring och i den här studien även fram till och med den andra gallringen.

Kommunägd skog i Sverige : en enkät- och intervjustudie av de tätortsnära skogarnas ekonomiska och sociala värde

This Masters thesis is performed at the request of the National Board of Forestry in order to investigate how the Swedish municipalities use their forests. The study is of general character with emphasis on the social values of the forests. The municipalities? purposes with their forests have varied over time, but lately the social aspects have been recognised as interesting. The social values of the forests can be defined as the values from the forests that contribute to the wealth of humans. This has socio-economic importance for the municipalities. The study was performed as a quantitative questionnaire survey, complemented with qualitative interviews.

Biogasproduktion genom tvåstegsrötning av drankvatten

During the 19-century a global warming has been observed, which includes increases in global air and ocean temperatures, widespread melting of ice and snow, and rising global sea level. There is a clear connection between emissions of greenhouse gases caused by the human and the increase in temperature. Climatic changes caused by global warming can be stopped trough decreased emission of fossil fuels, for example by an increased use of biogas. Biogas is a renewable energy source which is produced through anaerobic (oxygen free) digestion of organic material. The gas is a mixture of methane (CH4) and carbon dioxide (CO2) and can be among others used as fuel in vehicles.

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